Snap action closure with concentric annular flex zones

ABSTRACT

A plastic container has a bottom wall; upstanding side walls; a snap acting top wall with a dispensing opening, said top capable of flexing in two concentric annular zones to assume two stable positions; and a diaphragm across the upper portion of said container just below said top wall, said diaphragm having at least one perforation around the periphery thereof. The top is snapped into a convex up position to dispense the contents through the perforations and thereafter through the dispensing opening, and is snapped into a concave down position to close the container. This container primarily comprises parts fabricated from sheet material by thermoforming and die cutting.

United States Patent Collie Apr. 1, 1975 I SNAP ACTION CLOSURE WITH3.260.425 7/1966 Moran 222/541 3,321.1 l4 5/1967 Croyle 222/499CONCENTRIC ANNULAR FLEX ZONES [75] Inventor: Stafford D. Collie, GlenEllyn, Ill.

[73] Assignee: Phillips Petroleum Company,

Bartlesville. Okla.

[22] Filed: Apr. 7, 1970 [2|] Appl. No.: 26,257

Related U.S. Application Data [63] Continuation-impart of Ser. No.682,260, Nov. l3,

i967, abandoned.

[521 U.S. Cl. 222/499 [5 l l Int. Cl B65d 35/44 [58] Field of Search222/499, 559, 570, 523, 222/525, 54]

I 56] References Cited UNITED STATES PATENTS [358.414 5/l934 Bogeaus222/499 Primary Examiner-Allen N. Knowles Ass/slam Examiner-Norman L.Stack, Jr.

[57] ABSTRACT A plastic container has a bottom wall; upstanding sidewalls; a snap acting top wall with a dispensing opening, said topcapable of flexing in two concentric annular zones to assume two stablepositions; and a diaphragm across the upper portion of said containerjust below said top wall, said diaphragm having at least one perforationaround the periphery thereof. The top is snapped into a convex upposition to dispense the contents through the perforations andthereafter through the dispensing opening, and is snapped into a concavedown position to close the container. This container primarily comprisesparts fabricated from sheet material by thermoforming and die cutting.

1 Claim, 4 Drawing Figures PAIENTEIJAPR 1 ms 3 874.567

' sum 1 pg 2 F/G. I 1 FIG. 2

INVENTOR.

S. D. COLL IE A TTORNEVS PATENTED 3.874.567

sum 2 of 2 INVENTOR. S. D. COLL! E A TTORNEVS SNAP ACTION CLOSURE WITHCONCENTRIC ANNILAR FLEX ZON CROSS REFERENCE TO RELATED INVENTION 'l hisis a continuation-in-part of copending patent application Ser. No.b81260. filed Nov. l3. I967 now abandoned BACKGROUND OF INVE TION Thisinvention relates to a snap action closure type dispensing container.

The advent of plastic containers has made it possible to provideconsumer goods in packages embodying functional and aestheticallypleasing designs. More durable packages and packages which betterprotect the contents are also possible. for instance, by virtue of thelow moisture permeability of certain plastic materials such as thepolyolefins. While such packages are finding widespread acceptance.consumers demand in ad dition greater convenience in opening packagesthan ever before. especially in dispensing containers. Since plasticcontainers must compete with paper and the like. there is an additionalrequirement in a plastic con tainer that it provide all of thesefeatures and at the same time be reasonably competitive from an economicpoint of \ie\\' with the older containers of the prior art. It isapparent that a closure device with mov ing or separate parts.particularly nonplastic parts such as springs and the like. is notdesirable. Even a screwon cap more than doubles the cost of many suchcontainel's.

Thus. to fulfill all of the diverse requirements of a commerciallysuccessful dispensing container. parts made by complex moldingoperations such as injection molding must he avoided and the containerso designed that the inherent advantages from the standpoint of cost ofextruded sheet which can be thermoformed or die cut be utilized to themaximum extent in the fabrication of the container. Further. adispensing container should provide a positive seal on reclosure. arequirement not generally compatible with the requirement for easyopening and inexpensive fabrication.

SUMMARY OF THE INVENTION It is an object of this invention to provide adispensing container with a snap acting type closure which can befabricated from a small number of easily fabricated parts.

It is a further object of this invention to provide a dispensingcontainer which is easily opened and closed and which provides apositive seal on closing.

It is yet a further object of this invention to provide a dispensingcontainer made exclusively of parts fabricated from extruded sheet.

In accordance with this invention. a dispensing container which does notrequire injection molded parts is protidcd having a bottom wall:upstanding side walls; a diaphragm across the upper portion of said sidewalls. said diaphragm having at least one perforation near its peripheryand a solid center section. and a snap acting top all portion havingsurfaces tapering toward a dispensing opening. said top having twoconcentric annular flex zones and being capable of assuming two stablepositions. a convex open position and a concave position wherein thearea around said dispensing opening cooperates with said solid portionof said diaphragm to form a closed position.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings. forming a parthereof. wherein like reference characters depict identical parts in thevarious views.

FIG. I is a perspective view partly in section of a dispensing containeraccording to the instant invention with the snap action top part in theopen position;

FIG. 2 is a perspective view partly in section of the container of FIG.I with the snap acting top portion in the closed position.

FIG. 3 is an exploded view of an alternate embodiment of this inventionshowing one method of fabrication; and

FIG. 4 is an exploded view of a container according to this inventionshowing an alternate method of fabrication.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Any suitable thermoplasticmaterial can be used in the fabrication of the containers of the instantinvention such as polymers of at least one l-olefin. said 1- olefinhaving from 2 to 8 carbon atoms per molecule. poly(vinyl chloride)impact polystyrene. and the like. Preferred materials are polymers of al-olefin selected from the group consisting of ethylene. propylene.butene and mixtures thereof. Polypropylene is an especially preferredmaterial for the fabrication of the snap acting top portion because ofthe ease with which integral hinges can be produced from polypropylene.All of the parts of the container can be made of the same thermoplasticmaterial or different thermoplastic materials can be used for thevarious parts. It is also within the scope of an alternate embodiment ofthe invention to form the body of the container of a material other thanplastic such as paperboard; however. in all instances. it is absolutelyessential that the snap acting top portion be of a thermoplasticmaterial of sufficient flexibility to assume two positions andsufficient rigidity to be stable in each of these positions. preferablya polymer of l-olefin selected from the group consisting of ethylene.propylene. butene and mixtures thereof. more preferably polypropylene.

The containers of the instant invention are useful for packagingl'lowable granular products such as soap powder and the like and foodproducts such as salt. sugar. and the like. and some liquids.

Packages of the instant invention may be decorated. can carrypromotional material. or have a discardable outer package of cellophaneor the like over the entire container or over the dispensing opening.

While the containers of the instant invention are preferably circular.they can also be oval. square. rectangular. or the like.

The various parts of the container can be affixed together by varioustechniques such as solvent welding. spin welding. gluing or mechanicalsnapping into place. Spin welding is an especially preferred method ofaffixing the bottom or the snap acting top part. In some instances thediaphragm may be held in place mechanb cally by the snap acting toppart.

Perforations may vary in size or shape depending on the nature of thegranular material being packaged; if the material to be packaged ispowdery then the perforations will be small. with material having largergranules the perforations may be larger.

Referring now to FIGS. 1 and 2 there is shown a dispensing containerhaving a bottom wall 12. upstanding side walls l4 and a snap acting topwall I6: said snap top wall has sloping surface I8 between concentricannular flex zones 37 and 46 which slopes generally toward dispensingopening 20. A web 22 (an integral part of the top wall of the containeris the preferred embodiment) extends part of the way across dispensingopening to provide a means for grasping said snap acting top wall toopen the container. Diaphragm 24 extends across the upper portion ofsaid container just below said snap acting top wall. Diaphragm 24 hasholes or perforations 26 in an annular configuration around theperiphery of said diaphragm such that the dome-shaped center section 28of said diaphragm in the area corresponding to the position of saiddispens ing opening 20 when said snap acting top part is in the closedposition is solid. FIG. I shows the snap acting top part in the first ofits two stable positions, the open position. FIG. 2 shows the snapacting top part 16 in the second of its two stable positions. the closedposition.

As can be seen from FIG. 2. contact ofthe underside of the snap actingtop \\'all around the periphery of the dispensing opening with the topsurface ofthc solid. Linperforated central portion of diaphragm 24 alongline I9 prevents the contents coming through holes 26 from escapingthrough the dispensing opening. By top surface of the central portion ofdiaphragm 24 is meant the generally flat upper surface as opposed toside surfaces 27. This generally flat surface may be completely flat asin FIG. 3 ol' dome-shaped as in FIGS. I. 2 and 4. The container caneasily be opened by pulling up on web 22. and closed by depressing thecentral area of snap acting top wall I6.

Referring now to FIG. 3. there is shown an exploded view of thecontainer of the instant invention showing one of the alternate methodsof fabrication. In this em bodiment. upstanding side walls I4. snapacting top wall 16 and web I22 are formed as an integral unit by blowmolding and then cutting out bottom end 32. or more preferably by vacuumforming. In the case of vacuuming forming. bottom I I2 is fabricated asa separate member. In the case ofblow molding. it can he the POP tioncut out to form the open bottom end. Perforated diaphragm I24 is theninserted into the body portion 30 comprising the side walls I4. snapacting top wall I6. and web I22, through open bottom end 32 and affixedto said body portion across the top of the container near the topportion of upstanding side walls l4. (While it cannot be seen in thisview the bottom end 32 is open.) This may be done by gluing. spinwelding. or snapping the diaphragm into indentations fornted in the bodyportion during the fabrication of the body portionv The contents may beadded at this time or the bottom H2 may be affixed and the contentsadded later through the dispensing opening. Since the contents can beadded through the dispensing opening it is not essential that thepackage be filled prior to completion of the fabrication of thecontainer. Bottom II2 which forms bottom wall 12 on being affixed tobody portion 30 is affixed across open end 32 by gluing. heat fusion.solvent welding. or preferably by the specific heat fusion method ofspin welding. The dispensing opening 20 (not shown in FIG. 3) is thenformed by removing a portion of web I22. This may be done during thefabrication of the container or it may be left in place with only ascore line indicating the portion to be removed so as to form a sealwhich is removed by the consumer when the package is initially opened.It is apparent that in instances where the bottom H2 is affixed to openend 32 prior to filling the container that dispensing opening 20 must beprovided prior to the filling of the container. Diaphragm I24 and bottomI I2 are prefera bly formed from sheet material; thus in the embodimentswhere body portion 30 is thermoformed this entire highly complex.contoured. reclosable. dispensing container is fabricated frominexpensive. easily ex truded sheet material. In the embodiment shown inFIG. 3 the diaphragm is simply die cut from a flat sheet. This diaphragmhas a solid center section I28 corresponding to section 28 in the otherembodiments.

Referring now to FIG. 4. there is shown an alternate embodiment withregard to the method of fabricating the novel container of the instantinvention. In this embodiment there is provided body portion 34comprising upstanding side walls l4 and bottom wall [2. Body portion 34can be fabricated by means of blow molding or preferably by means ofthermoforming from sheet. Diaphragm 24 has large rectangular holes 26.domeshaped solid center section 28 and flange 36. Holes 26 may be round.rectangular, or any other suitable shape. Snap acting top I I6 whichbecomes the snap acting top wall 16 ofthe finished container has slopingsurface I8. dispensing opening 20. web 22. and annular inwardlyprojecting ridge 40. To assemble this container. diaphragm 24 ispositioned across the top of upstanding side walls I4 with llangc 36contacting the end portions of said walls. Snap acting top 116 is thenaffixed over open top end 42 of body portion 34 by means of inwardlyprojecting annular ridge 4" snapping into annular groove 44. These partscan also be affixed by gluing. solvent welding. spin welding. and thelike. Diaphragm 24 has large rectangular holes 26 and an upwardlyprojecting curved solid center section 28. The removal of the materialforming the large rectangular holes 26 gives the remaining webconnecting said dome-shaped solid center section 28 a spring effect sothat when the snap acting top wall assumes the downward stable positionand contacts domushaped solid center section 28 along annular flex zone46 said dome-shaped solid section can be depressed slightly to accountfor irregularities in the surface of the parts so as to effect apositive seal. The area of top [I6 forming inner flex zone 46 contactsthe dome-shaped solid center section as shown in FIG. 2 along line I9.

By comparing FIGS. I and 2, for instance. it can be seen that annularflex zones 37 and 46 form concentric integral hinges separated byannular surface I8. which hinges bend as the top wall snaps from onestable position to the other.

It is to be noted that both snap acting top [I6 and diaphragm 24. whilebeing separate elements. are both thermoformed from sheet material.Diaphragm 24 can also be a simple flat sheet which is simply die cut anddoes not undergo a thermoforming operation as in FIG. 3. Thus in thepreferred embodiment where body portion 34 is thermoformed. this entirecomplex. highly contoured. dispensing container is fabricated frominexpensive. easily extruded sheet material. Furthermore. since it ispossible to thermoform tough ultra high molecular weight polymer whichcannot be injection molded. the instant invention makes possible notonly lower cost containers but also containers ol'exceptional durabilityEXAMPLE A lb-ounce round bottle was blow molded from (L3 melt index(AS'l'M I.) l2384i2l'. (ondition l'i). 0.9M) density (AS'IM l)lSllS-(Lll polyethylene and the top cut out to gi\e a body portion suchas that shown in H0. 4.11 l t-mill sheet ol'(|.l melt flow tAS'lM Dl238- 621. ('ondition 1.) 0.905 density ASTM D l5tl5-b3'l') polypropylenewas vacuum formed into a diaphragm such as is shown in l"|(i. 4. Theholes were cut out in a post l'orming operation. A ZR-mill sheetidentical to that used in forming the diaphragm was vacuum l'ornied intoa snap acting top such as is shown in FIGS. 1. 2. and 4. The dispensingopening was cut out in a post forming operation. The diaphragm waspositioned .iver the open end of the body portion and the snap act- .ngtop affixed to the body portion by means of the in- .vardly projectingridge on the top portion fitting into :he annular groove on the bodyportion. (ilue was utiizcd to lurther secure the top portion to the bodypor- ;ion. This container was filled with finely powdered ioap throughthe dispensing opening. The resulting :ontainer was easily opened todispense the contents md was easily closed to t'orm a positive seal toprevent eakage ol' the contents. Because the center section of hediaphragm was dome shaped it was l'ound that the iowdered soap tended tofall back ol'tol' this solid secion so that a pull of powdered soap didnot blow up Ill 6 through the dispensing opening when the snap actingtop portion was closed.

While this invention has been described in detail for the purpose olillustration it is not to be construed as limited thereby but isintended to cover all changes and modifications within the spirit andscope thereol.

I claim:

I. A dispensing container containing a material to be packagedcomprising:

a bottom wall:

side walls upstanding from said bottom wall.

an integral. one-piece snap acting top wall connecting with said sidewalls. said top wall having a generally centrally located dispensingopening having a web extending part ol the way across said dispensingopening to provide a gripping means and being so contoured as to havetwo concentric annular integral hinges around said dispensing opening.said hinges being separated by an annular surface said hinges beingcapable of bending so that said top wall can assume two stablepositions. an open convex position. and a closed concave position:

a diaphragm across said container. positioned just below said top wall.said diaphragm having at least one hole around its periphery and furtherhaving a solid center section corresponding to the position of saiddispensing opening. a generally flat top surface ol said center sectioncooperating with said top to close said containers.

1. A dispensing container containing a material to be packagedcomprising: a bottom wall; side walls upstanding from said bottom wall;an integral, one-piece snap acting top wall connecting with said sidewalls, said top wall having a generally centrally located dispensingopening having a web extending part of the way across said dispensingopening to provide a gripping means and being so contoured as to havetwo concentric annular integral hinges around said dispensing opening,said hinges being separated by an annular surface, said hinges beingcapable of bending so that said top wall can assume two stablepositions, an open convex position, and a closed concave position; adiaphragm across said container, positioned just below said top wall,said diaphragm having at least one hole around its periphery and furtherhaving a solid center section corresponding to the position of saiddispensing opening, a generally flat top surface of said center sectioncooperating with said top to close said containers.